Automatic low-water-level marker.



W. DAUON.

AUTOMATIC LOW WATER LEVEL MARKER.

1 1 APPUCAT UN FI'LETJ SEPT. 21, I915- patpnted lMa-Y 2 SHEETS--SHEEI l.

INVENTOR W. DALTON.

AU;O:A+\TIC LOW WATER LEVEL MARKER INVENTOH Patented May 16, 1916.

2 SHEETS-SHLT 2 WITNESS WILLIAM DALTON, OF SCHENECTADY, NEW YORK.

AUTOMATIC LOW-WATER-LEVEL MARKER.

Specification of Letters Patent.

Patented May 16, 1916.

Original application filed May 15. 1914. Serial No. 838.681. Divided and this application filed September To Hi5 Whom it may concern ll it lalmfittl that I. Human Daixrox, of l ?ln l ?(l,zi l\', in the county of Schenectady and State New York, have invented a certain new and useful Improvement in Automatic Low-Watcr-Level Markers, of which inun-ovtmwnt the following a specification.

Mr invention relates to low water level UNll'liHl'S for steam boilers, particularly those operating on locomotive engines, and is designed to automatically present arrexterior indication or mark, in all variations of position of the boiler relatively to a normal horizontal one. which will correspond to a 'ncdetermincd sate level above the highest level of the crown sheet of the boiler.

'lhe object of my invention is to provide means whereby the permissible safe, low water level may be automatically and clearly indicated. regardless of variations of position of the boiler in operation, relatively to its normal horizontal position, such, for example, as are effected. by the of a locomotive from a level to a grade, or from a horizcontal portion of the track to one which is laterally inclined by the ole ration of the outer rails in curve, or vice ve; 4,, thereby guarding against destructive explosions and loss of life. due to the lack of a sr licieni, depth of tater above the crown oi the fir box.

Another object of the invention is to provide simple and effective means whereby the actual water level in a steam boiler may be at all times compared with the permissible sate low water level, irrespective of the size and working inclinations of the boiler, in order that the operator may feel certain as to the actual sate amount of water over the crown sheet, the tendency to carry an excess of water being tl'lcrcby avoided, and the boiler being relieved from the lmrdcn of heating an excessive amount of feed water when working at its maximum capacity in ascending a grade and preparatory to a suddcnrhange in its inclination when reaching the summit, thus enabling a greater amount of dry steam to be furnished at a higher evaporativo elliciency, with a corresponding material increase of economy and pflvl er.

A. further object is to provide means Serial No. 51.833.

whereby the accuracy and proper operation of the glass gage tube and gage cocks ordinarilv applied on locomotive boilers may be checked when the locomotive is under rolling or lateral swaying movement.

The improvement claimed is hereinafter fully set forth.

In the accompanying drawings: Figure l is a vertical longitudinal section, taken on the line A A of Fig. 2, through the rear or firebox end of a locomotive boiler, illustrating an application of my invention, the boiler being disposed in a level or horizontal position; big. 2, a rear end View. in elevation; Fig. 3. a section, taken similarly to Fig. 1, showing the boiler as in a slightly inclined position, as indicated by the angle between the central line and the adjacent lower horizontal line; Fig. 4, a vertical longitudinal central section, on an enlarged scale, through a locomotive boiler, illustrating the detailed construction and attachment of my invention as applied thereto, an intermediate portion of the firebox being broken away; and, Fig. 5, a partial rear view, in elevation, of the same.

My invention is herein exemplified as applied in a large locomotive boiler, of the scmi-wide firebox type, comprising, as in ordinary practice, a firebox, 1, which is closed at top by a crown sheet, 2, and is connected to a shell, 4, through which a plural-. ity of fire tubes, 3, extends from the tube sheet, 5, to a smoke box (not shown) at the front end of the boiler. As in all proerly designed boilers of this type, the hcig t of the water and steam space between the crown sheet and the shell, is necessarily comparatively limited to avoid excessive external dimensions of the boiler and afford the requisite clearance from bridges, tunnels, and vehicles on parallel tracks. In locomotives designed for heavy grade or mountain service, it is of special and urgent importance to insure the maintenance of a snfiicicnt depth of water over the crown sheet, particularly when operating at full power on heavy grades, to avoid risk of destructive explosions and resultant loss of life and damage to property. In practice, it is usual to allow approximately from three to four inches over the crown sheet, 2, (which is generally inclined downwardly toward the back head of the boiler), adjacent to the firebox tube sheet, 5, and it is clearly not within the bounds of prudence to assume that a safe allowance of water depth may be insured in a large locomotive boiler, having a length of as much as fortyone feet of water surface, by the mere obser vation f a water glass gage located on the back head, (3, of the boiler, which may be sixteen feet or more in 1' air of the critical point of level, which is at the highest level of the crown sheet where it fliljOlIl-i the tube sheet, 5.

By the descriptive term critical point", as hereinapplied, there is meant a point lo *atcd a minimum safe distance innnediately above the highest point of the crown sheet or other surface exposed to direct furnace heat, below which point the water level in the boiler must never, consistently with safety, be permitted to fall. This limitation of warranted assumption is particularly important when the locomotive is operating on mountain roads in which there are continual changes in the grades and curvature, and wherein the rail elevations on curves cause the locomotive to frequently sway from side to side.

To enable the operator to maintain a safe water depth over the crown sheet. my iiivention is designed to indicate. by observation at one or more points exterior to the boiler, a precise measure of the level of water at the critical point on the crown sheet, regardless of longitudinal or transverse inclination of the boiler.

In the n'actice of my invention, I provide a small reservoir, 7, which is supported within the boiler, preferably directl v over the crown sheet, '2, and adjacent to the firebox tube sheet, 5. The function of the single internal reservoir may, however, be performed by two separate reservoirs, located exterior to the boiler. as set forth in a separate application lilcd bv me May 15, 19H, Ser. No. RSSJESI, of which this application is a, division. pressure equalizatioii conduit of extra strong); pipe, 8. is con nectcd to the top of the reser oir and to a fastening member, J, scclli'cd by studs. 9, to the top of the shell, l, of the boiler. The conduit, 8, acting in combination with a liquid communication conduit. ll). and an indicator, 14, hereinafter described. constitutes an avenue through which equalization of pressure is established and maintained upon the liquid in tlureservoir. 7. and in the indicator. ll, thercbv causing said liquid to be at all times mainluincd at its original level. which is that of the critical point. A rcmovablc cap. fl. conncclcd to the top of the conduit. is provided for lbcpurpose of enabling a suitable lcvclinn' liquid. ll. which is preferably mercurv. to be supplied to the reservoir. The opening, if. in the boiler shell, through which the conduit, 8.

to be operated.

passes, is made sutliciently large to permit the removal of the reservoir, and small vent holes, 9", are formed in the fastening member, to maintain a tree opening for the conduit.

liquid C(Hllll'lllllitfiiijlv'fll conduit, 13, of extra strong pipe, extending above and substantially parallel with the crown sheet, 2, is connected, at one cud, to the bottom of the reservoir, 1', and, at the other to the lower end of a tubular indicator or automatic marker glass. ll, connected to and sup ported by the hack boiler head, l3. The corn duit, Ill, establishes free liquid connnuni cation between the reservoir, T, and marker glass, 14. and, acting in combination with the pressure equalization conduit, 8, in the normal horizontal position of the boiler, maintains the liquid surfaces, 11 and 15. in the reservoir and glass, respectively, at the same level, which is a predetermined distance above the critical point, 2, located preferabl at the highest level of the crown sheet, adjoining the firebox tube sheet, 5. The vertical distance between the liquid surface, 11, and the critical point. 2. is a measure of the safe allowable minimum depth f water over the crown sheet, and varies in amount in boilers of dili'ercnt designs and different service requirements.

The bore ofthc reservoir, i'.is greater, in a prcdctermincd ratio. than thatof the marker glass. ll. it will be obvious that if this ratio was indefinitely great. no change of elevation of the level of the liquid surfaces could taltc place relatively to the level of the critical point on the crown sheet. when the locomotive. in running forward, passes over the summit of a grade and moves on a down grade, as indicated in Fig. 3, The assumed relative inclination of the boiler, for example, as indicated in Fig. 3. compared with its normal horizontal or level position. as indicated in Fig". 1. being measured by the ang'lc formed b the center line. its, of the boiler and the horizontal line. 18', it. is important. in practice. lo insure greater safety by increasing the allowable depth of \YHtt-l' o\cr the crown sheet when the locomolivc boiler points down grade. in which operating, position the wat r leu-l naturally lowers over the crown shcct and rues at and toward the front or smok box tube sheet. in order to pro\ ide for this desirable increase. the proportionin; of thc rclatiw diameters of the reservoir and marh'oi' gl s is ba ed upon the dc-i :'n of thl boiler and the charact r of the service in which it is Thus. for illustration. if the aica of the b re of the rc cnoir. be. sa lhirtv times that of lhc bore of the marker glass. and the distance between the reservoir and class he. say, tiftccn feet. a dropof six inches in the level of the liquid surface in the glass would can-respond with an eleration of the liquid surfaces of one fifth of an inch. relati ely to the critical point. This I 5 be changed, by variation of ,the ratio of the bores in accordance with the structure and character of service of the boiler, which capacity of providing for change in the allowable water depth is an important and 9 valuable feature of my invention.

in the erection of a locomtive,-it is the usual pra tice, after the boiler ismounted in a level position on the locomotive frame, to l tflllidlltilltly secure to the back head, 6, 5 a his. onary marker, 20. which corresponds with the allowable safe minimum low water level ov r the critical point in the crown sheet. After the locomotive is under steam, at normal working pressure and-tempera- :o tare, after removing the cap, 9", the reservoir filled with mercury, until the liquid level therein. 11, reaches the elevation of the statiiimary marker, 20, after which the automatic marker can always be checked when the iiler is in a known level position. For poses of simplicity and ready ('fil'npitllnflil, the automatic marker glass, 14, is disposed parallel with and adjacent to the ordinary water gage glass, 21, and is secured to its support or mounting, 22. The lower end of the water gage glass is conncctcll with the boiler by a conduit, 23, secured into the back head, 6, and its upper end connected with the boiler by a pipe, 24., controlled by a valve, 25, in the usual manner. The upper end of the automatic marker glass, 14, is open to the atmosphere, and i. -otccted from grit and foreign mat: ter, by a cap, 14", which, together with the ot' the glass, 14, is supported in in which the glass is substantially by a bracket, 26, and the conduit, 23. The lower and of the glass, 14, is coupled to the conduit. 3, v a pipe elbow, 27, a union. 28, and pi flange, 29, which is fitted with a ball jointed connection, 30, engaging ball formed on the end of the conduit, 13.

Vl'h n desirable under service requirenents, the caps, 14 and 9*, are removed, -:nd a conduit. 32, shown in broken lines, is Minna-(ted to the pressure equalization -=ipc, 3, and the upper end of the marker .iilas i l. so as to establish and maintain :ann'iunicatimi between them, and form vith the liquid communication conduit, 13, and the reservoir, 7, a complete intercom- A lg circuit, whereby evaporation of liquid is avoided, and the originally equality of pressure thereon is :aintained, in the case Where the pipe, 8,

open to the atmosphere.

Under normal working conditions, the "ter surface, 33, in the glass, 21, corresponds in elevation with the actual water with the rear head, 6, of the boiler,

surface, 33, within the boiler, and the difference (shown by the line 34) in the elevation of the liquid surfaces in the glasses, 14 and 21, gives. an accurate measure of the excess of water level in the boiler above the permissible minimum safe low water level. The liquid surfaces, 33 and 15, will simultaneously rise and fall in a given inclination of the boiler, the relative amount of movement depending largely upon the design ofthe boiler, and the most desirable design giving the smallest change in the distance indicated by the line 34, other things being equal. This feature of my invention is of value in the comparison and selection of designs of boilers most suitable for railroads having many changes in grade. A graduated marker, combined with the fixed marker, 20, and indicating percentage of grade, is useful and-convenient for determining the track grade.

The complete appliance is preferably mount ed as near as possible to the vertical longitudinal central plane of the boiler, for the purpose of avoiding the distorting iniuence of side inclination or swaying, as the locomotive passesover elevations of the outer rails or curves.

My invention is of substantial practical merit and value in the particular of providing ready and effective means for detecting at all times any defect in the operation of the water level indicators ordi narily applied to locomotive boilers, as, for example, when a water gage cock or a water glass fitting becomes clogged by sediment or scale formation, a comparison of the relative positions and movement of the leveling liquid and the water level indicator reading will promptly show defective operation of the water level indicator. In such case, the movement of the water in the gage is relatively sluggish, and induces false readings, which are not in correspondence with the changing inclinations of the boiler. The latter are quickly and accurately indicated by the inclosed and protected leveling liquid.

I claim as my invention and desire to secure by Letters Patent:

1. The combination, with a steam boiler of a type which is subject to rolling or pitching motion in service, of a water level marker comprising an indicator outside the boiler, a reservoir located at a critical point within the boiler and adapted to contain a portion of a leveling liquid, said reseriroir being so said indicator and reservoir, and W whereby equal pressure may be maintained on the surfaces of the liquid in the reservoir and in the indicator.

2. The combination, with a steam boiler of a type which is subject to rolling or pitching motion in service, of a water level marker comprising an indicator outside the boiler, a reservoir located at a critical point within, and substantially in the longitudinal central plane of, the boiler, said reservoir being closed as against boiler pressure and adapted to contain a portion of a leveling liquid, and being so proportioned relatively to said indicator and so disposed as to establish a relatively large leveling liquid surface at a level corresponding with that of the critical point, said indicator being adapted to contain another portion of such liquid, a liquid communication conduit connecting the lower portions of said indicator and reservoir, and means whereby equal pressure may be maintained on the surfaces of the liquid in the reservoir and in the indicator.

3. The combination, with a steam boiler of a type which is subject to rolling or pitching motion in service, of a water level marker comprising an indicator outside the boiler, a reservoir located at a critical point Within the boiler and adapted to contain a portion of a leveling liquid, said reservoir being so proportioned relatively to said indicator and so disposed as to establish a relatively large leveling liquid surface at a level corresponding with that of the critical point, said indicator being adapted to contain another portion of such liquid, a liquid communication conduit extending above the crown sheet of the boiler, and connecting the lower portions of said indicator and reservoir, and means whereby equal pressure may be maintained on the surfaces of the liquid in the reservoir and in the indicator.

4. The combination, with a steam boiler of a type which is subject to rolling or pitching motion in service, of a Water level marker comprising an indicator outside the boiler, a

reservoir located at a critical point within the boiler and adapted to contain a portion of a leveling liquid, said reservoir being so proportioned relatively to said indicator and so disposed as to establish a relatively large leveling liquid surface at a level corresponding with that of the critical point, said indicator being adapted to contain another portion of such liquid, a liquid communication conduit connecting the lower portions of said indicator and reservoir, and a pressure equalization conduit extending from the reservoir through the shell of the boiler to the indicator.

WILLIAM DALTON. Witnesses:

CLEMENT J. CONTANDIE, HoRA'rIo N. \Voon. 

